Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative treatment for some patients with acute myeloid leukemia (AML). Whether older patients with AML benefit from curative potential of HCT similar to younger patients is not well understood. To understand this issue, we evaluated the impact of age and remission status on 242 consecutive patients that underwent HCT between 1999 and 2011 in our program. Based on age and remission status, patients were divided into 4 groups: Gp 1, CR1 age <60 (n=116); Gp 2, CR1 age ≥60 (n=32); Gp 3, CR2 age <60 (n=78); and Gp 4, CR2 age ≥60 (n=16).
Median age of all patients was 48 years (range 18–71), 123 patients (51%) were male. Peripheral blood stem cells were used in 178 patients (74%), bone marrow in 64 patients (26%). Donors were matched related (n=155, 64%) or matched unrelated (n=87, 36%). Median follow up of survivors was 65 months (range 12–145). No significant difference was found in terms of cytogenetic risk distribution between the 4 groups (p=0.14). Of the 48 patients ≥60 years of age, 46 (96%) received reduced-intensity conditioning regimens.
Survival at 2-years in Gp 1, Gp 2, Gp 3, Gp 4 was 59%, 43%, 43% and 23%, respectively (Fig 1). Corresponding relapse free survival (RFS) was 59%, 34%, 40%, and 19%, respectively. Cumulative incidence (CI) of relapse in the four groups was 14%, 34%, 21% and 25% respectively. The corresponding CI of non-relapse mortality (NRM) was 27%, 31%, 38% and 56% respectively. In a univariate analysis, the hazard ratios for survival for Gp 2, Gp 3 and Gp 4 were 1.488, 1.533 and 2.718 in reference to Gp 1, respectively.
Our data demonstrate that patients ≥60 years with AML in CR1 benefit from curative potential of HCT. Due to high NRM, patients ≥60 years in CR2 do not appear to benefit from curative potential of HCT. Therefore, if in an older patient HCT is indicated, attempts should be made to deliver the HCT in CR1.
No relevant conflicts of interest to declare.
Asterisk with author names denotes non-ASH members.